Improvement in piano-fortes



PETER SCHULER, OF PHILADELPHIA, PENNSYLVANIA.

IMPROVEMENT IN PIANO-FORTES.

Specification forming part of Letters Patent No. 58,896, dated October 16, 1866.

To all lwhom it may concern:

Be it known that I, PETER SGBULER, of the city of Philadelphia, in the State ot' Pennsylvania, have invented a new and useful Improvement in thePiano-Forte; and I do hereby declare that the following is a full, clear, and exact description of the construction and operation of the same, reference being had to the accompanying drawings, making a part of' this specification, in which- Figure lis a plan view of an open piano without its strings and keys; Fig. 2, a like view of the same, having its iron brace-plate removed; and Fig. 3, an enlarged longitudinal section of Fig. 1, like letters of reference indicating the same parts when in the different figures.

The sound-board of a piano has heretofore been glued fast at each end to the solid framebloeks of the case, and consequently the hygrometric changes in the atmosphere produce variations in its dimensions across the grain of the wood of the board, and therefore an end pressure, which causes it to buckle or bend downward, so as to impair its requisite elasticity, and from the same cause-the rigidlyiixed condition of both ends of the soundboard-a permanently-buckled or downwardbent condition of the same is, in a year or two, produced by the strain ofthe strings, notwithstanding the resisting support of the usual iron brace-plate, and the warped or counterarched construction ot' the frame in the line of the said strain.

The object of my improvement is to entirely obviate this very injurious effect upon the sound-board ot' a piano; and my invention consists, substantially as hereinafter described, in securing the said board in such a manner iu its bearings that it will, under the circumstances just recited, always retain its original straight elastic condition.

In the drawings, A is the usual metallic brace-plate; B, the usual sound-board, and C C C the usual solid frameblocks of' the case.

Instead of gluing the ends of the soundboard B down fast upon the blocks C, as heretofore, I glue a narrow strip of woolen cloth, felt, or other similar material, c1 c1, along on the bottom of each of the rabbets made in the blocks C, and then lay the sound-board down upon the said cloth or felt, and secure the smaller end, b, of the saine in its rabbet by screwing down upon it a block of Wood, et, having a layer of the said cloth or felt glued to its under side, thus fixing the said smaller end of the board B directly between two layers of the said cloth or felt. (See Fig. 3.) The broader end, b2 bz, of the said sound-board B, I then adjust in place, givingita little endplay, and lay over it two narrow strips, cii c, of vulcanized gum-elastic or other suitably solid and elastic material, having their under sides covered with the said cloth or felt, the said strips c3 being of such a thickness as will, with the layer of cloth or felt attached, canse them, when so laid, to reach a little above the upper surface of the. supporting-blocks C. I then lay down upon them the iron brace-plate A, and secure it by means of screws, so as to cause it to press down firmly upon the elastic strips c e, and thus clamp the board B directl y between the upper and lower layers of the cloth or felt, so as to secure it firmly down in place. (See Fig. 3.)

Opera-tion: The larger end b2 of thc soundboard having a little end-play in its rabbets, or heilig made so as toI be a. little short, and being tixed at its smaller end, b', the larger end, b2, will slide between the upper and lower layers of cloth or felt, when any change is produced in the said board B, either by hygrometric changes in the atmosphere or by a yielding of the frame ot' the piano from the strain of the strings, and consequent-ly the said sound-board will constantly maintain its original straight and elastic condition, as required.

This is a very important and desirable improvement in the piano, as it will eliectually preserve the original straight, and therefore elastic, condition of the said board, and thus prevent the tone of the instrument from degcnerating to the nasal sound consequent upon the buckling of the said board.

Having thus fully described my improvement, what I claim as new and of my invention, and desire to secure by Letters Patent, 1s-

Securing the sound-board of a piano between elastic or compressible bearings el c, so that one end of the same may slide between its bearings, substantially in the manner described and set forth, for the purpose specitied.

P. SCHULER.

Witnesses:

BENJ. MolusoN, B. F. SHATTUCK. 

